This is the temperature rise of the air inside an air-filled trough.

Symbol
$\Delta \theta_{\mathrm{tr}}$
Unit
K
Formulae
$T_{\mathrm{tr}} W_{\mathrm{sum}}$
Related
$T_{\mathrm{tr}}$
$W_{\mathrm{sum}}$
Used in
$\theta_{\mathrm{at}}$